/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.predictionio.examples.java.recommendations.tutorial4;

import org.apache.predictionio.controller.java.LJavaServing;
import org.apache.predictionio.controller.java.EmptyParams;
import java.lang.Iterable;

public class Serving extends LJavaServing<EmptyParams, Query, Float> {
  public Serving() {}

  public Float serve(Query query, Iterable<Float> predictions) {
    float sum = 0.0f;
    int count = 0;
    
    for (Float v: predictions) {
      if (!v.isNaN()) {
        sum += v;
        count += 1;
      }
    }
    return (count == 0) ? Float.NaN : sum / count;
  }
}

